Power generation system for an electronic system

ABSTRACT

An electronic system includes an electronic system cabinet housing at least one electronic system component and a power generation system. The power generation system includes a cooling system having a cooling medium that generates a cooling energy. The power generation system further includes a thermoelectric conversion element having a first side and a second side. The first side is in a heat exchange relationship with the at least one electronic system component and the second side is in a heat exchange relationship with the cooling medium. Heat energy generated by the at least one electronic system component raises a temperature of the first side and the cooling energy generated by the cooling medium lowers a temperature of the second side to establish a temperature difference. The thermoelectric conversion element produces an electro-motive force based on the temperature difference.

BACKGROUND

This invention relates to the art of electronic systems and, moreparticularly, to a system for generating power from heat produced by anelectronic system.

Conventionally, electronic systems such as computer servers, are cooledby means of forced air convention. Air conditioners generate a coolingair flow that is directed into cabinets housing the servers. In order toprovide additional cooling, liquid cooling systems pass a cooling fluidthrough the cabinets. The cooling fluid aides the forced air convectionin dissipating heat. As data centers increase in size, thermal energyoutput from the servers, in the form of exhaust gases, increasessignificantly.

SUMMARY

In accordance with an exemplary embodiment of the invention, anelectronic system includes an electronic system cabinet having at leasttop, rear and opposing side walls defining an electronic system zone, atleast one electronic system component housed in the electronic systemzone. The at least one electronic system component produces heat energy.The electronic system also includes a power generation system mounted tothe electronic system cabinet. The power generation system includes amain housing attached to one of the top, rear and opposing side walls ofthe electronic system cabinet, and a cooling system arranged within themain housing. The cooling system includes a cooling medium thatgenerates a cooling energy. The power generation system further includesa thermoelectric conversion element arranged within the main housing.The thermoelectric conversion element includes a first side and a secondside. The first side is in a heat exchange relationship with the atleast one electronic system component and the second side is in a heatexchange relationship with the cooling medium. The heat energy generatedby the at least one electronic system component raises a temperature ofthe first side and the cooling energy generated by the cooling mediumlowers a temperature of the second side to establish a temperaturedifference. The thermoelectric conversion element produces anelectro-motive force (EMF) based on the temperature difference.

In accordance with another exemplary embodiment of the invention, Amethod of generating power using heat produced by an electronic systemincludes operating at least one electronic system component, the atleast one electronic system component producing a heat energy,circulating a cooling medium through a cooling system to create acooling energy, exposing a first side of a thermoelectric conversionelement to the heat energy, exposing a second side of a thermoelectricconversion element to the cooling energy to establish a temperaturedifference in the thermoelectric conversion element, and generating anelectro-motive force (EMF) based on the temperature difference in thethermoelectric conversion element.

In accordance with yet another exemplary embodiment of the invention, apower generation system for an electronic system includes a mainhousing, and a cooling system arranged within the main housing. Thecooling system includes a cooling medium that generates a coolingenergy. The power generation system also includes a thermoelectricconversion element arranged within the main housing. The thermoelectricconversion element includes a first side and a second side. Heat energygenerated by at least one electronic system component raises atemperature of the first side and the cooling energy generated by thecooling medium lowers a temperature of the second side to establish atemperature difference. The thermoelectric conversion element producingan electro-motive force (EMF) based on the temperature difference.

Additional features and advantages are realized through the techniquesof exemplary embodiments of the present invention. Other embodiments andaspects of the invention are described in detail herein and areconsidered a part of the claimed invention. For a better understandingof the invention with advantages and features, refer to the descriptionand to the drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The subject matter which is regarded as the invention is particularlypointed out and distinctly claimed in the claims at the conclusion ofthe specification. The foregoing and other objects, features, andadvantages of the invention are apparent from the following detaileddescription taken in conjunction with the accompanying drawings inwhich:

FIG. 1 is an electronic system cabinet including a power generationsystem in accordance with exemplary embodiments of the invention;

FIG. 2 is a partial, cross-sectional schematic view of the electronicsystem cabinet and power generation system of FIG. 1;

FIG. 3 illustrates a thermoelectric conversion element of the powergeneration system of FIG. 2; and

FIG. 4 is a flow chart illustrating a method of generating power inaccordance with exemplary embodiments of the invention.

The detailed description explains the exemplary embodiments of theinvention, together with advantages and features, by way of example withreference to the drawings.

DETAILED DESCRIPTION

With initial reference to FIGS. 1 and 2, an electronic systemconstructed in accordance with exemplary embodiments of the invention isindicated generally at 2. Electronic system 2 includes an electronicsystem cabinet 4 having a main body 6. Main body 6 includes top, bottom,opposing side and rear walls 8-12 that collectively define an electronicsystem zone 14. Cabinet 4 also includes a door 16 that selectivelyprovides access to electronic system zone 14. Cabinet 4 is also shown toinclude a plurality of electronic system components 21-23. In theexemplary embodiment shown, electronic system components take the formof computer servers. However, it should be readily understood thatelectronic system components 21-23 can take a variety of forms. In anyevent, as each electronic system component is similarly formed, adetailed description will be made referencing electronic systemcomponent 21, with an understanding that the remaining electronic systemcomponents 22-23 are similarly formed. Of course, the other electronicsystem components could also differ without departing from the spirit ofthe invention.

As best shown in FIG. 2, electronic system component 21 includes a mainboard 26 having mounted thereto a memory chip 28, a processing unit 30and a fan 33. In operation, processing unit 30 produces heat energy. Fan33 draws in an air flow, indicated by a plurality of arrows (notseparately labeled) through, for example door 16, over processing unit30 to absorb the heat energy. The air flow containing the heat energy isthen passed through rear wall 12. Of course, it should be understoodthat the particular location of fan 33 could vary. As will be discussedmore fully below, the heat energy produced by each electronic componentis converted into electrical energy. Towards that end, electronic system2 includes a power generation system 40 mounted to rear wall 12 ofelectronic system cabinet 4. It should also be realized that theparticular mounting location of power generation system 40 can vary inaccordance with exemplary embodiments of the invention.

In accordance with the exemplary embodiment shown, power generationsystem 40 includes a main housing 44 having top, rear, and opposing sidewalls 46-49. Power generation system further includes a power generationcontrol unit 55 operatively connected each fan 33 and to a plurality ofthermoelectric conversion elements 64-66. As each thermoelectricconversion element is constructed similarly, a detailed description willfollow with reference to FIG. 3 in describing thermoelectric conversionelement 64. In the exemplary embodiment shown, thermoelectric conversionelement 64 comprises a Seebeck element 67 including a first side 68 anda second, opposing, side 69. First side 68 is formed from a first metalor semiconductor and second side 69 is formed from a second, distinctmetal or semiconductor. One of the first and secondmetals/semiconductors is a N-type material having a negative temperaturecoefficient, while the other of the first and secondmetals/semiconductors is a P-type material having a positive temperaturecoefficient. First side 68 is connected to second side 69 such that whena temperature differential exists, thermoelectric conversion element 64produces an electro-motive force (EMF). The strength of theelectro-motive force depends on the types of metals/semiconductorsutilized on each side 68, 69 as well as the magnitude of the temperaturedifferential.

In further accordance with the exemplary embodiment, power generationsystem 40 includes a cooling system 71 having a cooling medium conduit73. Cooling medium conduit 73 includes a first end portion 76 thatextends to a second end portion 77 through an intermediate portion 78.Cooling medium conduit 73 is fluidly connected to a plurality of heatexchange members 83-85. Each heat exchange member 83-85 adjoins acorresponding second surface 69 of each thermoelectric conversionelement 64-66. Heat exchange members 83-85 can be in either a directheat exchange relationship with each thermoelectric conversion element64-66, i.e., directly contact a corresponding second surface 69, or inan indirect heat exchange relationship with each thermoelectricconversion element 64-66, i.e., a thermal interface material (TIM) (notshown) is present between each heat exchange member 83-85 thecorresponding second surface 69. With this arrangement, a cooling mediumcontrol unit 89 pumps a cooling medium such as, but not limited to,water, through cooling medium conduit 73. The cooling medium controlunit is operatively connected to power generation control unit 55 and isselectively operated in response to the temperature difference betweeneach first and second side 68 and 69. That is, cooling medium controlunit 89 pumps the cooling medium at a desired rate into each heatexchange member 83-85 to deliver cooling energy to each second surface69. In this manner, surface temperature of each second surface islowered.

In still further accordance with the exemplary embodiment, powergeneration system 40 includes a plurality of air guides 94-96 arrangedbetween corresponding ones of each thermoelectric conversion element64-66, and rear wall 12 of electronic system cabinet 6. Air guides 94-96directed the air flow containing the heat energy from each electronicsystem component 21-23 onto respective a respective first side 68 ofeach thermoelectric conversion element 64-66. More specifically, eachthermoelectric conversion element 64-66 includes a corresponding heatexchange fin 98-100 mounted in a heat exchange relations with each firstside 68 of thermoelectric conversion elements 64-66. Air guides 94-96guide the air flow containing the heat energy onto heat exchange fins98-100. In this manner, surface temperature for each first surface 68 iselevated. With this configuration, a thermal difference is establishedat each thermoelectric conversion element 64-66. The thermal differencecauses each thermoelectric conversion elements 64-66 to produce anelectro-motive force. The elector-motive force is passed to a DC/ACconverter 104 and used to power electrical devices.

Reference will now be made to FIG. 4 in describing a method 200 ofgenerating power with power generation system 40. Power generationcontrol unit 55 senses for a temperature difference is greater than atemperature difference required for power generation at eachthermoelectric conversion element 64-66 as indicated in block 202. If atemperature difference is of sufficient magnitude, power is generated asindicated in block 204, if the temperature difference is not ofsufficient magnitude, power generation control unit 55 senses whethereach first side 68 is at an established hot temperature limit value forpower generation. If any first side 68 is below the hot temperaturelimit value, power generation control unit 55 increases a speed of thecorresponding fan 33 as indicated in block 208. A determination is thenmade whether the temperature difference is of sufficient magnitude forpower generation as indicated in block 210 and, if so, power isgenerated as indicated in block 212. If not additional checks are madeas discussed below.

In addition to determining that all first sides 68 are at the hottemperature limit value, a determination is made whether each secondside 69 is at a cold temperature limit value for power generation asindicated in block 214. If any second side 69 is above the coldtemperature limit value, power generation control unit 55 increases aflow rate of the cooling medium by increasing output from cooling mediumcontrol unit 89 as indicated in block 216. A determination is then madewhether the temperature difference is of sufficient magnitude for powergeneration as indicated in block 218 and, if so, power is generated asindicated in block 220. If not, power generation control unit 55continues monitoring until the temperature difference is of sufficientmagnitude for power generation so that power can be generated. At thispoint it should be realizes that the exemplary embodiments of theinvention provide a simple cost effective mechanism for utilizing heatenergy from exhaust gases generated in an electronic system cabinet tocreate additional power that is used to operate various electricaldevices such as, but not limited to, Uninterruptible Power Supply (UPS)units, mobile devices, battery chargers, and to secure electric powerfor illumination and/or air conditioning.

The flow diagram depicted herein is just an example. There may be manyvariations to this diagram or the steps (or operations) describedtherein without departing from the spirit of the invention. Forinstance, the steps may be performed in a differing order, or steps maybe added, deleted or modified. All of these variations are considered apart of the claimed invention.

While the preferred embodiment to the invention has been described, itwill be understood that those skilled in the art, both now and in thefuture, may make various improvements and enhancements which fall withinthe scope of the claims which follow. These claims should be construedto maintain the proper protection for the invention first described.

1. An electronic system comprising: an electronic system cabinet havingat least top, rear and opposing side walls defining an electronic systemzone; at least one electronic system component housed in the electronicsystem zone, the at least one electronic system component producing heatenergy; and a power generation system mounted to the electronic systemcabinet, the power generation system including: a main housing attachedto one of the top, rear and opposing side walls of the electronic systemcabinet; a cooling system arranged within the main housing, the coolingsystem including a cooling medium that generates a cooling energy; athermoelectric conversion element arranged within the main housing, thethermoelectric conversion element having a first side and a second side,the first side being in a heat exchange relationship with the at leastone electronic system component and the second side being in a heatexchange relationship with the cooling medium, wherein the heat energygenerated by the at least one electronic system component raises atemperature of the first side and the cooling energy generated by thecooling medium lowers a temperature of the second side to establish atemperature difference, the thermoelectric conversion element producingan electro-motive force (EMF) based on the temperature difference; andan air guide mounted between the electronic system zone and thethermoelectric conversion element, the air guide directing the heatenergy from the at least one electronic system component toward thefirst side of the thermoelectric conversion element.
 2. The electronicsystem according to claim 1, wherein the cooling system includes acooling medium conduit having a first end portion extending to a secondend portion through an intermediate portion, the intermediate portionextending though the main housing adjacent the electronic system zone.3. The electronic system according to claim 2, wherein the coolingmedium conduit is fluidly connected to at least one heat exchangemember, the at least one heat exchange member adjoining the secondsurface of the thermoelectric conversion element.
 4. The electronicsystem according to claim 2, wherein the cooling system includes acooling medium control unit, the cooling medium control unit circulatingthe cooling medium through the cooling medium conduit.
 5. The electronicsystem according to claim 2, wherein the cooling medium comprises one ofwater and a refrigerant.
 6. (canceled)
 7. The electronic systemaccording to claim 1, wherein the power generation system includes aplurality of heat exchange fins mounted to the first side of thethermoelectric conversion element, the plurality of heat exchange finsguiding the heat energy from the at least one electronic system onto thefirst side of the thermoelectric conversion element.
 8. The electronicsystem according to claim 1, wherein the thermoelectric conversionelement is a Seebeck element.
 9. The electronic system according toclaim 1, further comprising: a DC/AC converter electrically connected tothe thermoelectric conversion element.
 10. (canceled)
 11. (canceled) 12.(canceled)
 13. A power generation system for an electronic system, thepower generation system comprising: a main housing; a cooling systemarranged within the main housing, the cooling system including a coolingmedium that generates a cooling energy; a thermoelectric conversionelement arranged within the main housing, the thermoelectric conversionelement having a first side and a second side, wherein heat energygenerated by at least one electronic system component raises atemperature of the first side and the cooling energy generated by thecooling medium lowers a temperature of the second side to establish atemperature difference, the thermoelectric conversion element producingan electro-motive force (EMF) based on the temperature difference; andan air guide directing heat energy from the at least one electronicsystem component toward the first side of the thermoelectric conversionelement.
 14. The power generation system according to claim 13, whereinthe cooling system includes a cooling medium conduit having a first endportion extending to a second end portion through an intermediateportion, the intermediate portion extending though the main housingadjacent the electronic system zone.
 15. The power generation systemaccording to claim 14, wherein the cooling medium conduit is fluidlyconnected to at least one heat exchange member, the at least one heatexchange member adjoining the second surface of the thermoelectricconversion element.
 16. The power generation system according to claim14, wherein the cooling system includes a cooling medium control unit,the cooling medium control unit circulating the cooling medium throughthe cooling medium conduit.
 17. The power generation system according toclaim 14, wherein the cooling medium comprises one of water and arefrigerant.
 18. (canceled)
 19. The power generation system according toclaim 13, further comprising: a plurality of heat exchange fins mountedto the first side of the thermoelectric conversion element, theplurality of heat exchange fins guiding the heat energy from the atleast one electronic system component onto the first side of thethermoelectric conversion element.
 20. The power generation systemaccording to claim 13, wherein the thermoelectric conversion element isa Seebeck element.